Building Apps
Packaging Source Code
Usage
enact pack [options]
Options
-p, --production Build in production mode
-i, --isomorphic Use isomorphic code layout
(includes prerendering)
-w, --watch Rebuild on file changes
-l, --locales Locales for isomorphic mode; one of:
<commana-separated-values> Locale list
<JSON-filepath> - Read locales from JSON file
"none" - Disable locale-specific handling
"used" - Detect locales used within ./resources/
"tv" - Locales supported on webOS TV
"signage" - Locales supported on webOS signage
"all" - All locales that iLib supports
-s, --snapshot Generate V8 snapshot blob
(requires V8_MKSNAPSHOT set)
--stats Output bundle analysis file
Run within an Enact project’s source code, the enact pack
command (aliased as npm run pack
or npm run pack-p
for production) will process and bundle the js, css, and asset files into the ./dist
directory. An index.html file will be dynamically generated.
Production Mode
By default, projects will build in development mode. When you’re code is ready for deployment you can build in production mode. Production mode will minify the source code and remove dead code, along with numerous other minor code optimization strategies.
__DEV__ Keyword
In order to make development and debugging simpler, the enact cli supports a special __DEV__
keyboard in both javascript and CSS.
In javascript, for example:
if (__DEV__) {
console.log('This is a development build');
}
In development mode, the code will execute correctly, whereas in production mode it will get caught and removed as unused dead code. This allows for custom development-only debug code.
Similarly, in css/less:
div .__DEV__ {
background: blue;
}
}
In development mode, the css/less remains intact and usable, but in production mode, the .__DEV__
css class stylings are removed. This allows for custom development-only styling.
Isomorphic Support & Prerendering
By using the isomorphic code layout option, your project bundle will be outputted in a versatile universal code format allowing potential usage outside the browser. The enact cli takes advantage of this mode by additionally generating an HTML output of your project and embedding it directly with the resulting index.html. By default, isomorphic mode will attempt to prerender only en-US
, however with the --locales
option, a wade variety of locales can be specified and prerendered. More details on isomorphic support and its limitations can be found here.
V8 Snapshot Generation
The v8 snapshot blob creation feature is highly experimental and tempermental depending on your code. It is considered an extension of the isomorphic code layout, bringing along all the same requirements. Given the highly-specific nature of a v8 snapshot blob being tied to particular versions of Chrome/Chromium/Electron/etc., developers must provide their own copy of the mksnapshot
binary and have its filepath set to the V8_MKSNAPSHOT
environment variable.
Watcher Option
Similar to the enact serve
command, the watcher will build the project and wait for any detected source code changes. When a change is detected, it will rebuild the project. The rebuild time will be significantly faster since the process can actively cache and build only what has changed.
Stats Analysis
The Bundle analysis file option uses the popular webpack-bundle-analyzer to create a visual representation of the project build to stats.html, showing the full module hierarchy arranged by output size. This can be very useful in determining where bloat is coming from or finding dependencies that may have been included by mistake.